#include<iostream>
#include<vector>
using namespace std;

class Solution {
    int ret;
    bool check[16];
public:
    int countArrangement(int n) {
        dfs(1, n);
        return ret;
    }

    void dfs(int pos, int n)
    {
        if (pos == n + 1)
        {
            ret++;
            return;
        }

        for (int i = 1; i <= n; i++)
        {
            if (check[i] == false && (i % pos == 0 || pos % i == 0))
            {
                check[i] = true;
                dfs(pos + 1, n);
                check[i] = false;
            }
        }
    }
};